holes, fittings ok...
do your fittings thread together, or are they just stuffed in the hole?
if it threads together, use a rubber o-ring on the "inside" part, that is the part in the water. slip the o-ring around over the hole, and then assemble your pieces together, make sure to compress the o-ring some but not to the point that it's distorted.
if your fitting is stuffed in the hole, no amount of glueing will help in my opinon, as any time you touch the fitting to take hose on or off, it will stress the glue and could cause a leak. If you really want to try glue, sand everything with some 60 grit sand paper (coarse), and then use something like JB Weld or Weld-On #16 - should make a water tight seal, but I don't know about how strong it will be.